When it comes to hand-held tuners that modify the factory tune on a mildly upgraded Mopar Hemi, the Predator was the tuner of choice for nearly a decade. At the time of its introduction, the Predator was an advanced tool that provided the enthusiast an opportunity to modify the factory software and take advantage of the potential of newly installed bolt-on parts. As time progressed, DiabloSport dropped the aging Predator, but after a few years’ hiatus, the Predator is back. The new Predator, called the Predator P2 (part No. 7301, $329.95, retail), is an all-new design that extends the legacy of the Predator. According to Matt Barker of DiabloSport: “The Predator P2 is a completely redesigned piece of hardware compared to the original Predator.” Barker continued, “It has a full color screen, a lightning-fast user interface, and a broader vehicle coverage for each sku.” The Predator P2 is a premium tuner packaged in a comfortable ergonomic case with a five-button controlled navigation screen, which provides great tuning capabilities at a low cost.”

Barker explains: “With simple upgrades like an intake or exhaust, the pre-built tuning in the P2 will work great. When you start making internal engine modifications, forced induction, use race fuel, or bigger cams, then you may need a custom tune.” With the relatively stock test car used in this story—a 2006 5.7L Hemi Charger—the 50-state compliant tuner with the built-in tunes would meet our needs. The Charger has been a test bed for a series of evaluations over the last year. Currently, the Hemi has SOS coils from Performance Distributors, AMSOIL products throughout the drivetrain, a pair of TTI long-tube headers and full exhaust, and a Trickflow underdrive damper installed. If a Hemi has radical engine changes, DiabloSport offers the Predator P2 Pro Performance Programmer, which includes the DiabloSport tuning built in, and has the ability to accept a Chip Master Revolution (CMR) custom tune, provided by independent dealers. If you feel your Hemi may be too extreme for the 50-state compliant P2, visit DiabloSport.com for guidance.

When the Predator arrived, the package included the P2 tuner and integrated OBDII cable, a USB cable to connect to a PC with internet access for product updates, a California Air Resources Board (CARB) Executive Order (E.O.) No. D-770 sticker (to be placed in the glovebox or affixed to the driver’s side door jamb), an instruction manual, and a DiabloSport sticker. Before any tuning could begin, the P2 required a software download. With the P2 connected via the USB cable to a PC and the installation software installed on the PC, the P2 was registered, and an “Ignition” shortcut icon was installed on the PC’s desktop. Clicking on the “Ignition” icon started the software program and any updates for the Predator automatically downloaded. If additional options were available, the user could select the options. Once all the updates were completed, the “Ignition” software signaled on the PC’s screen that all the P2 updates were finalized. Now we were ready to use the Predator!

The Charger was strapped to the Pennsylvania College of Technology’s Mustang chassis dynamometer. With the Hemi and the drivetrain warmed up, three pulls were performed to establish a baseline. All three runs were within 1 percent of each other with a best baseline of 343 lb-ft of torque from 4,200-4,500 rpm and a peak of 317 hp at 5,200 rpm. With the baseline established, the P2 was connected to the OBDII port under the dash of the Charger. After the P2 powered up, we followed the screen prompts in the “Tune” menu which gave us the choice of selecting one of two pre-built tunes to upload to the Charger’s Powertrain Control Module (PCM). We selected the Diablo Tune, which would maximize the engine and transmission output while requiring 93-octane fuel. The other tune was a 91-octane tune. Depending upon your vehicle, a Diablo Tow mode tune, an 87-octane performance tune, and an 87-octane fuel economy tune may be optional selections. With 93-octane in the tank and the Diablo Tune installed, the Hemi twisted the Mustang’s rollers three more times. The results were impressive and repeatable. All three runs were within 1 percent of each other. The increase in peak torque was 17 lb-ft to 360 lb-ft at 4,600 rpm. The peak horsepower rose to 332 hp at 5,200 rpm for an increase of 15 hp. Throughout the entire pull, the average increase in torque was 14 lb-ft, and the average horsepower increase was 12 hp. A best of 23 lb-ft of torque increase was seen at 3,500 rpm, and the best increase of 18 hp was at 5,300 rpm.

With solid numbers from the P2, we explored the advanced tuning options. The P2 allows the modification of the canned tunes within certain parameters to attempt to increase the Hemi’s output. The advanced tuning options allowed the modification of the engine idle, gear ratio, speed limiter, rev limiter, tire size, automatic transmission shift points and shift (line) pressure, cooling fans operation, skip shift (manual transmissions), spark advance, and Multi-Displacement System (MDS) cylinder deactivation. Adjusting the spark advance did not improve upon the Diablo Tune provided in the P2. The altering of the shift points and line pressures provided very little in terms of horsepower or torque gain but may show promise at the dragstrip. Deactivating the MDS allowed all the cylinders to operate 100% of the time. The relatively stock Hemi seem to operate best with the 93-octane tune. If there had been more dyno time or the Hemi had been stouter, the advanced tuning operations may have had greater output.

After the performance tests, the P2 was used to return the PCM to the stock tune. From the “Tune” menu, we found the stock tune, and within minutes, the stock tune reloaded to the PCM without any indication of a software change having ever occurred. This is a recommended procedure whenever the vehicle requires service, so the repair center does not flash (reprogram) an update to the PCM that will limit the ability of the P2 to communicate with the PCM due to a software mismatch.

Whenever the Charger wheels roll on the chassis dyno, several ABS and traction control Diagnostic Trouble Codes (DTCs) are set, and their corresponding warning lights illuminate on the instrument cluster. The Predator has a “Scan” menu option to read the DTCs, and once repaired, can clear these codes. The navigation buttons allowed us to see that seven DTCs had been set. With the touch of button, the P2 erased all the codes. The P2 lists each DTC by the OBDII compliant P0XXX code. Any online reference provides a description of the code and a brief repair procedure.

Additional uses of the P2 are gauge display and data logging. If there is a need to monitor a particular Parameter ID (PID), the P2 can be set up to display that PID. The P2 “Scan” menu allows the monitoring of a total of eight PIDs within eight groups at one time. The PID data can be recorded and then viewed later to evaluate the current tune of the engine.

Besides tuning and scanning, the P2 provides the user with important information (Info menu) about the vehicle such as the VIN, tuning level, and vehicle files. Additionally, the P2 will provide device information from the same menu. The information includes sku, app, database version, and other device parameters. This provides the user with information about the latest update applied to the P2.

Is the Predator P2 as good as the original Predator? Hands down, the P2 is better. It is faster, more powerful, and has a better viewing screen than the original. The P2 is an inexpensive way to get dyno-proven performance increases while not requiring a deep understanding of the theories of engine tuning. The P2 provides manufacturer scan tool capabilities, data logs for optimizing tunes, and provides detailed information about the vehicle and itself. The ease of use and the great performance potential of the P2 makes the tuner the only tuner most aficionados will ever need.

This makes me want to crack open the tune on my HEMI to see what I can do.